Thermostat



E. W. BALLENTINE THERMOSTAT Filed Dec. 3, 1951 B/-METHL 'Patented ocr. 24, 41933 PATENT OFFICE THERMOSTAT Earle W. Ballentine, Chicago, Ill., assignor to Solar Industries, Inc., Chicago, Ill., a corporaj-A tion of Illinois Application December 3, 1931. Serial No. 578,815

2 Claims.

This invention relates to thermostats and, more especially, such a device employing .a natural magnet in order to give a snap action or accelerated make and break.

` For the purpose of illustrating my invention, I am showing the same embodied in a two-contact thermostat, although it is obvious that the principles may be employed in a single-contact device.

Among the features of my invention is the provision of improved mounting and arrangement f the parts affording protection to the bi-metal element and strength, rigidity and durability to the instrument.

; Another feature of the invention is the provision of a horseshoe magnet with its closed end attached to the base and its poles curved upwardly and backwardly with their ends lying above the base. This permits the use .of a magnet with relatively long legs or poles without unduly increasing the width of the device. This arrangement of the magnet also' permits easy adjustment thereof.

Another feature of the invention is the arrangement of the temperature-adjusting levers above the bi-metal element,'thus serving as a.

protection for the latter.

Other features and advantages of my invention will appear more fully as I proceed with my specification.

In that form of device embodying the features of my invention shown in the accompanying drawing- Figure 1 is a top plan view with the cover attached; Fig. 2 is a similar view on an enlarged scale with the cover removed; Fig. 3 is a view in side elevation showing the cover in section; Fig. 4 is a view taken as indicated by the line 4-4 of Fig. 3; Fig. 5 is a view taken as indicated by the line 5--5 of Fig. 2; Fig. 6 is a fragmentary view of the underside of the device; and Fig. 7 is a. view taken as indicated by the line 7-'7 of Fig. 4.

For convenience in description, it will be assumed that the device is lying as shown in the drawing, of which Figure 1 is a top plan view.

As shown in the drawing, the device includes a base 10 provided with a removable cover 11.

Adjustably mounted on the base 10 is a horseshoe magnet with its closed end 12 adjustably attached to the base 10 by the bolt 13, the head 13 of said bolt engaging the rectangular washer 14 lying over the magnet. As indicated, the poles cf the magnet are curved upwardly and backwardly as shown by 15, with their ends 16, 16

lying above the base 10. The magnet may be Y carrying the bi-metal element.

shifted laterally for adjustment by loosening the bo t 13.

Numeral 17 indicates a U-shaped carrier for This carrier is pivotally attached to the base by the bolt 18. 19 indicates a spiral-shaped bi-metal element attached to the member 24 by the rivet 20, said member 24 being attached to the carrier 17. l

Numeral 21 indicates an armature attached 'to the bi-metal element and lying adjacent the ends of the poles of the magnet.

Numerals 22, 22 indicate a pair of adjustable contact points mounted 'on the base and lying adjacent the armature, one on each side thereof.

Numeral 23 indicates a temporary adjusting lever attached to the bi-metal carrier and lying above the bi metal element 19. As here shown, this lever 23 is integral with the carrier and forms a continuation of the same, the bi-metal element 19 being attached to the carrier by the additional arm 24. 25 indicates a second temperature-adjusting lever pivotally attached to the base at 26 and pivotally attached to the lever 23 at 27. The free end of the lever 25 has its end 28 bent upwardly and extending through a slot .29 inthe cover 11. Movement of the end 28 will swing the temperature-adjusting levers to swing thev car rier 17 to alter the position of the bi-metal element 19 and the armature 21 thus permitting adjustment of the device. The magnet is ordinarily adjusted so that the armature 21 will lie close to the ends of the poles but not touch the same. This will give the armature an accelerated or snap action as it moves into or out of the magnetic iield. The armature 21 is provided with the usual contact piece 30 to engage the contact points 22, 22.

The construction of the thermostat as above shown permits rigid mounting of the magnet and contacts on the base. This contributes to the accuracy of the instrument. 'Ihe adjustment is effected by swinging the carrier 17 which supports the bi-metal element 19. This adjustment can be made very accurately due to the compound lever arrangement shown.

While I'have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from. the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention to claim all novelty inherent in my invention as 'brQadly as permissible, in view of the prior art.

What I regard as new, and desire to secure by Letters Patent, is:

1. A thermostat, including; a base; a horseshoe magnet with its closed end attached to the base and its poles curved upwardly and backwardly with their ends lying above the base; a bi-rnetal element carrier pivotally attached to the base, the axis of the pivot being perpendicular to the base; a bi-metal element carried by the carrier; an armature attached to the bi-metal element and lying adjacent the ends of the poles of the mag- EARLE W. BALLENTINE. 

